Hi,
I have a similar issue that probably is the same bug? Thought I'd share, just in case.
If I add a mp4 video file from my gopro its is in stereo, but if I add a mp3 music file from Youtubes library, I can suddenly only hear the mp4 video in the left channel. The mp3 is stereo.
If I remove the mp3 music file, the mp4 videos sound is back in both channels.
Is it the same bug?